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More than a hundred-thousand lives could be saved each year if a readily available blood-clotting drug were administered to people who had suffered serious bleeding injuries or with surgical complications. Tranexamic acid (TXA), an off-patent drug, inhibits clot breakdown, and while some research suggests it increases the risk of cardiac arrest, stroke, and pulmonary thrombosis, the benefits in terms of controlling critical bleeding quickly might offset this risk. Indeed, the CRASH-2 trial, a large, randomized trial with more than 20,000 adult patients in 274 hospitals across 40 countries, showed no evidence of adverse effects caused by clotting.

A new strain of yeast, TMB3130, developed by evolutionary engineering can efficiently ferment pentose sugars, xylose and arabinose, from agricultural waste and hardwoods into ethanol. Marie Gorwa-Grauslund, from Lund University, Sweden, and colleagues, used recombinant Saccharomyces cerevisiae to produce the new strain by introducing genes from bacteria and fungi that allow pentose metabolism. The research could lead to a simple way to produce second-generation biofuels that do not require a supply of virgin crop grown for fuel rather than food.

Canadian researchers have turned to metal crystals bring order to organic materials, which could overcome a principal stumbling block in the development of nanoscale electronics. So far the team at McGill University has used a copper surface to template the polymerization of one-dimensional strands of material, as revealed by scanning probe microscopy. They hope to extend their approach to two dimensions in order to create organic graphite sheets, which they say might one day lead to nano chips a single molecule thick in which individual transistors would be ten times smaller than those available in conventional semiconductor electronics today.

Direct observations that the rings of rotaxanes, which consist of a mechanically interlocked macrocycle encircling a dumbbell-shaped thread, can shuttle back and forth in response to a stimulus have been made by an international team. By pinning the ends of a rotaxane to a gold surface the researchers were able to control the supramolecular entity sufficiently to be able to use scanning tunneling microscopy to observe the shuttling of the macrocycle between different "stations" on the thread. Such evidence, as opposed to indirect spectroscopic studies, ultimately improves the potential for using these molecules as so-called molecular machines.

Powerful yet portable spectrometers would allow analytical work to be carried out in the field more easily, whether in medical diagnostics, environmental research or forensic science. Now, researchers at RWTH Aachen, Germany, have developed a magnetic system that fits in the palm of your hand and could allow portable high-resolution nuclear magnetic resonance (NMR) spectroscopy to be carried out without the hindrance of otherwise bulky magnets. The new configuration of magnets can easily accommodate a standard NMR tube and so has the additional benefit of allowing samples of a conventional volume to be analyzed readily.

1999 Nobel chemist Ahmed Zewail of Caltech receives the 2011 Priestley Medal awarded by the American Chemical Society Board of Directors at its June meeting. This is the ACS's most prestigious award and is given this year in recognition of Zewail's development of revolutionary methods for the study of ultrafast processes in chemistry, biology, and materials science.